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Despite coal-power output in the US falling to its lowest level in nearly 60 years, the nation’s greenhouse gas emissions fell by just 0.2% in 2024, according to new research from the Rhodium Group

Increases in electricity demand and continued growth in transport emissions led to US emissions remaining broadly “unchanged”, while the economy grew by 2.7%, the New York-based research group finds.

The US is the world’s second-largest annual emitter, has very high per-capita emissions and by far the greatest historical responsibility for current warming.

Even though emissions remained unchanged from a year earlier, they were still 8% below pre-pandemic levels in 2024 and remained about 20% below 2005 levels, Rhodium notes.

While the pace of decarbonisation slowed in 2024, after a reduction of 1.9% in 2023, new policies and regulations introduced under the Biden administration were expected to see this accelerate in the coming years, Rhodium says. 

However, it notes that this progress could now be at risk from the incoming presidency of Donald Trump. Trump has repeatedly pledged to roll back a range of environmental policies brought in by his predecessor Joe Biden. 

Solar and wind overtake coal

Renewable energy in the US grew in 2024, with the combined output from solar and wind surpassing coal in the electricity mix for the first time ever, according to Rhodium.

Together, solar and wind made up 16% of the electricity mix in 2024, up nearly two percentage points from 2023. Solar generation grew by 32% and wind by 7%, both outpacing the 4% growth in gas generation, the report notes.

Solar had a record-setting year in 2024, accounting for 64% of all new electricity-generating capacity added to the US grid in Q3, according to the Solar Energy Industries Association.

However, the rollout of wind generation was hit by notable challenges, including increased costs and project siting difficulties.

Gas-fired electricity generation remained the single-largest source in the US by far, producing a record 1,782 terawatt hours (TWh) in 2024, some 43% of the total.

Nuclear was the second-largest, as shown in the figure below. It generated 781TWh, some 19% of the total, just ahead of the combined output of wind and solar, as well as coal.

The electricity generation mix in the US, showing gas, nuclear, combined solar and wind, coal, hydro and other sources in terawatt -hours, 2005-2024. Source: Rhodium Group, EIA.

The growth of wind and solar helped ensure that the generation mix was “slightly cleaner” in 2024, even though demand for electricity rose by 3%, says Rhodium.

Buildings represented the biggest increase in demand for electricity, where a 10% growth in “cooling degree days” – a measure of how hot the temperature is – drove up summer electricity use. (The US saw record-breaking heatwaves across the year, with the summer of 2024 the hottest on record, the Guardian reported.)

After buildings, industry ranked second and commercial buildings third as the biggest sources of increased electricity demand.

There has been a lot of media focus on artificial intelligence (AI) driving electricity demand growth. Moreover, a Department of Energy-commissioned study in December found that US data centre power demand could nearly triple within four years, consuming as much as 12% of the country’s electricity by 2028.

However, Rhodium notes that data centres were only a small source of demand growth in 2024, representing just a fraction of the third biggest source of electricity demand.

In 2024, the additional power demand was met by gas, wind and solar, while coal continued to decline, dropping one percentage point to 16% of the electricity mix.

In absolute terms, coal provided as much power in 2024 as it did in 1967 when Lyndon Baines Johnson was the 36th president of the US, the Vietnam War was raging and Elvis Presley married Priscilla Ann Beaulieu in Las Vegas. 

Gas remained the single largest source of power in the US in 2024, accounting for 43% of the total (1 percentage point higher than in 2023), notes Rhodium.

This growth – to meet increased demand – offset the reduction in coal generation and emissions from the power sector increased by 0.2% (3m tonnes of carbon dioxide equivalent, MtCO2e) in 2024.

Alongside the increase in renewable energy, the US saw record-high investment in the manufacturing and deployment of clean technologies last year, Rhodium says.

For example, investment in clean technologies accounted for 5% of total private investment in structures, equipment and durable consumer goods in the third quarter of last year, according to the latest data from the Clean Investment Monitor

Crude oil production was up by 2.4% in 2024, while gas production fell by 0.6%, according to Rhodium. This was a slightly bigger drop in gas production than in 2020 when the Covid pandemic hit, as producers reacted to lower prices by drilling fewer new wells and curtailing production, it adds.

The research estimates that oil and gas systems released around 10% less methane per unit of output in 2024 than in 2022, due to cleaner production practices as well as state and federal regulations.

As such, cleaning up oil and gas production led to a 3.7% drop in emissions from the sector, some 11MtCOe relative to 2023.

Hurricanes hit industrial emissions

Industrial emissions fell in 2024 due to low manufacturing output, Rhodium finds. Across the year, the sector’s emissions fell by 1.8%, or 22MtCO2e, from 2023.

Chemicals, computers and electronics, and paper production grew in 2024, but declines in food and beverages, mining and machinery offset these gains, it says.

This included historically low coal mining activity, which fell by 12% in 2024 to its lowest level in decades due to demand falling, as coal power plants retire and are replaced by renewables and gas, as noted in the section above.

One factor in declining industrial output was extreme weather. Along with the impact of labour disruption on production, Hurricanes Beryl, Milton and Helene also all hit manufacturing output, notes Rhodium. 

Transport remained the highest-emitting sector in the US, with a 0.8% increase in emissions driven by post-pandemic rebounds in jet fuel and petrol consumption, according to Rhodium.

Emissions from transport, industry and buildings have remained relatively steady in recent decades, whereas the power sector has seen steady declines, as shown in the figure below.

Emissions across key US sectors including transport, power, industry, buildings, agriculture and oil and gas show in million tonnes of CO2e
Emissions across key US sectors including transport, power, industry, buildings, agriculture and oil and gas show in million tonnes of CO2e. Source: Rhodium Group, EPA.

Available seat miles” – a metric used to quantify air travel – set a new record in 2024, up 6% year-on-year in the first three quarters of the year, according to Rhodium. 

There was also “record-high road activity” the report notes, with a 1% increase in road traffic volumes up to October. As such, petrol consumption increased, although diesel continued to fall, dropping close to 2020 levels.

Despite these increases in transportation activity, emissions from the sector still remain 2.%% below 2019 levels.

Building sector emissions increased by 0.4% due to elevated fuel use, Rhodium adds.

Looking ahead

The “modest 2024 decline underscores the urgency of accelerating decarbonisation in all sectors” concludes Rhodium, in particular with the imminent change in US government.

Currently, the US is not on track to meet either its 2030 Paris Agreement target of a 50-52% reduction in emissions relative to 2005 levels or its newly set 2035 goal of a 61-66% reduction. 

To bridge the gap between the current US trajectory and its stated goals would require an average emissions reduction of 7.6% every year from 2025 through to 2030, says Rhodium. This would be more than two-thirds of the drop seen as a result of Covid lockdowns in 2020.

US net emissions trajectory (2000-2025), highlighting the progression needed to reach the Copenhagen Accord and Paris Agreement climate targets.
US net emissions trajectory (2000-2025), highlighting the progression needed to reach the Copenhagen Accord and Paris Agreement climate targets. Source: Rhodium.

Analysts, including Rhodium, have predicted that the combined impact of the Inflation Reduction Act (IRA), Infrastructure Investment and Jobs Act and Environmental Protection Agency (EPA) regulations on vehicles and power plants will increase the pace of emissions reductions in the future. 

There is already some evidence of this, with the most recent data from Clean Investment Monitor suggesting that clean energy and transportation investment could reach a high of $71bn in the third quarter of 2024. 

This would cap the “nearly unbroken streak of quarter-on-quarter growth since the IRA’s passage, with clean investment now accounting for a record 5% of total US private investment”, notes Rhodium.

However, whether the rate of emissions reduction actually accelerates is heavily dependent on the extent to which the incoming Trump administration and the Republican Congress rollback and repeal EPA regulations and energy and tax policies brought in or expanded through the IRA.

Trump has repeatedly promised to pull back climate policies, saying in September 2024 that “to further defeat inflation, my plan will terminate the Green New Deal, which I call the Green New Scam” in reference to the IRA, according to Politico

In December, Rhoiodum published a separate piece of research dubbed: “Trump 2.0: What’s in Store for US Energy and Climate?” It explored a number of potential pathways the Trump administration could pursue when he takes office on 20 January, including one called “rollbacks and repeal”. 

This pathway would see the pace of US decarbonisation slow significantly, leaving emissions at 24-40% below 2005 levels in 2035. This is equivalent to roughly an additional 1bn tonnes of CO2e in 2035 in each emissions scenario explored by Rhodium.

Rolling back regulations alone could lead to a 270-470MtCO2e increase in emissions by 2035, it adds. This would represent 25-50% of the total emissions increase under the full “rollbacks and repeal” pathway.

Analysis by Carbon Brief in March 2024 found that Trump winning November’s presidential election could lead to a cumulative additional 4bn tonnes of US emissions by 2030, compared to under Bidens’s plans. 

Ben King, co-author of the preliminary emissions analysis and Trump 2.0 note, and an associate director in Rhodium Group’s energy and climate practice, tells Carbon Brief:

“It’s not clear what precise policy actions the Trump administration and Republican-controlled Congress will take, but we analysed the potential impacts of two major policy changes: rolling back major climate regulations from the Environmental Protection Agency (EPA) and repealing the energy and tax policies that were enhanced and expanded through the Inflation Reduction Act (IRA). Rolling back EPA climate regulations alone – which the Trump administration could pursue unilaterally, though not immediately – could increase greenhouse gas emissions by 270-470MtCO2e in 2035.

“A more extreme policy pathway, rolling back EPA regulations and immediately repealing the energy and tax components of the IRA – which would require congressional approval – could increase emissions by nearly 1GtCO2e in 2035.”

Rhodium concludes its analysis of the US’s emissions in 2024 by noting that it will be watching developments around ​​rolling back and repealing climate policies “closely”.

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Explainer: Why gas plays a minimal role in China’s climate strategy

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Ten years ago, switching from burning coal to gas was a key element of China’s policy to reduce severe air pollution.

However, while gas is seen in some countries as a “bridging” fuel to move away from coal use, rapid electrification, uncompetitiveness and supply concerns have suppressed its share in China’s energy mix.

As such, while China’s gas demand has more than doubled over the past decade, the fuel is not currently playing a decisive role in the country’s strategy to tackle climate change.

Instead, renewables are now the leading replacement for coal demand in China, with growth in solar and wind generation largely keeping emissions growth from China’s power sector flat.

While gas could play a role in decarbonising some aspects of China’s energy demand – particularly in terms of meeting power demand peaks and fuelling heavy industry – multiple factors would need to change to make it a more attractive alternative.

Small, but impactful

The share of gas in China’s primary energy demand is small and has remained relatively unchanged at around 8-9% over the past five years.

It also comprises 7% of China’s carbon dioxide (CO2) emissions from fuel combustion, according to the International Energy Agency (IEA).

Gas combustion in China added 755m tonnes of CO2 (MtCO2) into the atmosphere in 2023 – double the total amount of CO2 emitted by the UK.

However, its emissions profile in China lags well behind that of coal, which represented 79% of China’s fuel-linked CO2 emissions and was responsible for almost 9bn tonnes of CO2 emissions in 2023, according to the same IEA data.

Gas consumption continues to grow in line with an overall uptick in total energy demand. Chinese gas demand, driven by industry use, grew by around 7-8% year-on-year in 2024, according to different estimates.

This rapid growth is, nevertheless, slightly below the 9% average annual rise in China’s gas demand over the past decade, during which consumption has more than doubled overall, as shown in the figure below.

Chart showing China's gas consumption has doubled in a decade
Total demand for gas in China, 1965-2024, billion cubic metres. Source: Energy Institute statistical review of world energy 2025.

The state-run oil and gas company China National Petroleum Corporation (CNPC) forecast in 2025 that demand growth for the year may slow further to just over 6%.

The majority of China’s gas demand in 2023 was met by domestic gas supply, according to the Institute for Energy Economics and Financial Analysis (IEEFA).

Most of this supply comes from conventional gas sources. But incremental Chinese domestic gas supply in recent years has come from harder-to-extract unconventional sources, including shale gas, which accounted for as much as 45% of gas production in 2024.

Despite China’s large recoverable shale-gas resources and subsidies to encourage production, geographical and technical limitations have capped production levels relative to the US, which is the world’s largest gas producer by far.

CNPC estimates Chinese gas output will grow by just 4% in 2025, compared with 6% growth in 2024. Nevertheless, output is still expected to exceed the 230bn cubic metre national target for 2025.

Liquified natural gas (LNG) is China’s second most-common source of gas, imported via giant super-cooled tankers from countries including Australia, Qatar, Malaysia and Russia.

This is followed by pipeline imports – which are seen as cheaper, but less reliable – from Russia and central Asia.

One particularly high-profile pipeline project is the Power of Siberia 2 pipeline project. However, Beijing has yet to explicitly agree to investing in or purchasing the gas delivered by the project. Disagreements around pricing and logistics have hindered progress.

Evolving role

Beijing initially aimed for gas to displace coal as part of a broader policy to tackle air pollution.

A three-year action plan from 2018-2020, dubbed the “blue-sky campaign”, helped to accelerate gas use in the industrial and residential sectors, as gas displaced consumption of “dispersed coal” (散煤)”– referring to improperly processed coal that emits more pollutants. 

Meanwhile, several cities across northern and central China were also mandated to curtail coal usage and switch to gas instead. Many of these cities were based in provinces with a strong coal mining economy or higher winter heating demand.

China’s pollution levels saw “drastic improvement” as a result, according to a report by research institute the Centre for Research on Energy and Clean Air (CREA).

(In January 2026, there were widespread media reports of households choosing not to use gas heating despite freezing temperatures, as a result of high prices following the expiry of subsidies for gas use.)

Industry remains the largest gas user in China, with “city gas” – gas delivered by pipeline to urban areas – trailing in second, as shown in the figure below. Power generation is a distant third.

Chart showing that industry is the largest gas user in China, followed by residential gas sue
Gas consumption by sector in 2023, billion cubic metres. Source: China Natural Gas Development Report (2024).

Gas has never gained momentum in China’s power sector, with its share of power generation remaining at 4% while wind and solar power’s share has soared from 4% to 22% over the past decade, Yu Aiqun, a research analyst at the US-based thinktank Global Energy Monitor, tells Carbon Brief.

Yu adds that this stagnation is largely due to insufficient and unreliable gas supply, which drives up prices and makes gas less competitive compared to coal and renewables. She says:

“With the rapid expansion of renewables and ongoing geopolitical uncertainties, I don’t foresee a bright future for gas power.”

Average on-grid gas-fired power prices of 0.56-0.58 yuan per kilowatt hour (yuan/kWh) in China are far higher than that of around 0.3-0.4 yuan/kWh for coal power, according to some industry estimates. Recent auction prices for renewables are even cheaper than this.

Meanwhile, the share of renewables in China’s power capacity stood at 55% in 2024, compared with gas at around 4%.

Generation from wind and solar in particular has increased by more than 1,250 terawatt-hours (TWh) in China since 2015, while gas-fired generation has increased by just 140TWh, according to IEEFA.

As the share of coal has shrunk from 70% to 61% during this period, IEEFA suggests that renewables – rather than gas – are displacing coal’s share in the generation mix.

However, China’s gas capacity may still rise from approximately 150 gigawatts (GW) in 2025 to 200GW by 2030, Bloomberg reports.

A report by the National Energy Administration (NEA) on development of the sector notes that gas will continue to play a “critical role” in “peak shaving”, where gas turbines can be used for short periods to meet daily spikes in demand. As such, the NEA says gas will be an “important pillar” in China’s energy transition.

In 2024, a new policy on gas utilisation also “explicitly promoted” the use of gas peak-shaving power plants, according to industry outlet MySteel.

China’s current gas storage capacity is “insufficient”, according to CNPC, reducing its ability to meet peak-shaving demand. The country built 38 underground gas storage sites with peak-shaving capacity of 26.7bn cubic metres in 2024, but this accounts for just 6% of its annual gas demand.

Transport use

Gas is instead playing a bigger part in the displacement of diesel in the transport sector, due to the higher cost competitiveness of LNG as a fuel – particularly in the trucking sector.

CNPC expects that LNG displaced around 28-30m tonnes of diesel in the trucking sector in 2025, accounting for 15% of total diesel demand in China.

This is further aided by policy support from Beijing’s equipment trade-in programme, part of efforts to stimulate the economy.

However, gas is not necessarily a better option for heavy-duty, long-haul transportation, due to poorer fuel efficiency compared with electric vehicles (EVs).

In fact, “new-energy vehicles” (NEVs) – including hydrogen fuel-cell, pure-electric and hybrid-electric trucks – are displacing both LNG-fueled trucks and diesel heavy-duty vehicles (HDVs).

In the first half of 2025, battery-electric models accounted for 22% of all HDV sales, a year-on-year increase of 9%, while market share for LNG-fueled trucks fell from 30% in 2024 to 26%.

Gas can be cheaper than oil but is not competitive with EVs and – with the emergence of zero-emission fuels such as hydrogen and ammonia – gas may eventually lose even this niche market, says Yu.

Supply security

Chinese government officials frequently note that China is “rich in coal, poor in oil and short of gas” (“富煤贫油少气”). Concerns around import dependence have underpinned China’s focus on coal as a source of energy security.

However, Beijing increasingly sees electrification as a more strategic way to decarbonise its transport sector, according to some analysts.

“Overall, electrification is a clear energy security strategy to reduce exposure to global fossil fuel markets,” says Michal Meidan, head of the China energy research programme at the Oxford Institute for Energy Studies.

Chinese oil and gas production grew dramatically in the last few years under a seven-year action plan from 2019-25, as Beijing ordered its state oil firms to ramp up output to ensure energy security.

Despite this, gas import dependency still hovers at around 40% of demand. This, according to assessments in government documents, exposes the country to price shocks and geopolitical risks.

The graph below shows the share of domestically produced gas (dark blue), LNG imports (mid-blue) and pipeline imports (light blue), in China’s overall gas supply between 2017 and 2024.

Chart showing that China produces most of its gas domestically, but imports around 40% of its supply
China’s gas supply by source, 2017-2024, billion cubic metres (bcm). Source: IEEFA.

“Gas use is unlikely to play a significant role in decarbonising the power system, but could be more significant in industrial decarbonisation,” Meidan tells Carbon Brief.

She estimates that if LNG prices fall to $6 per million British thermal units (btu), compared to an average of $11 in 2024-25, this could encourage fuel switching in the steel, chemical manufacturing, textiles, ceramics and food processing industries.

The chart below shows the year-on-year change in gas demand between 2001-2022.

Chart showing that industrial gas demand rising overall, although some years see growth slowing
Year-on-year changes in Chinese industry’s gas demand by sector, 2001-2023, bcm. Source: National Bureau of Statistics (NBS), OIES.

Growth in gas demand has been decelerating in some industries in recent years, such as refining. But it also remains unclear if Beijing will adopt more aggressive policies favouring gas, Meidan adds.

A roadmap developed by the Energy Research Institute (ERI), a thinktank under the National Development and Reform Commission’s Academy of Macroeconomic Research, finds that gas only begins to play an equivalent or greater role in China’s energy mix than coal by 2050 at the earliest – 10 years ahead of China’s target for achieving carbon neutrality.

Both fossil fuels play a significantly smaller role than clean-energy sources at this point.

Wang Zhongying and Kaare Sandholt, both experts at the ERI, write in Carbon Brief:

“Gas does not play a significant role in the power sector in our scenarios, as solar and wind can provide cheaper electricity while existing coal power plants – together with scaled-up expansion of energy storage and demand-side response facilities – can provide sufficient flexibility and peak-load capacity.”

Ultimately, China’s push for gas will be contingent on its own development goals. Its next five-year plan, from 2026-2030, will build a framework for China’s shift to controlling absolute carbon emissions, rather than carbon intensity.

Recent recommendations by top Chinese policymakers on priorities for the next five-year plan did not explicitly mention gas. Instead, the government endorses “raising the level of electrification in end-use energy consumption” while also “promoting peaking of coal and oil consumption”.

The Chinese government feels that gas is “nice to have…if available and cost-competitive but is not the only avenue for China’s energy transition,” says Meidan.

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Explainer: Why gas plays a minimal role in China’s climate strategy

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Guest post: 10 key climate science ‘insights’ from 2025

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Every year, understanding of climate science grows stronger.

With each new research project and published paper, scientists learn more about how the Earth system responds to continuing greenhouse gas emissions.

But with many thousands of new studies on climate change being published every year, it can be hard to keep up with the latest developments.

Our annual “10 new insights in climate science” report offers a snapshot of key advances in the scientific understanding of the climate system.

Produced by a team of scientists from around the world, the report summarises influential, novel and policy-relevant climate research published over the previous 18 months.

The insights presented in the latest edition, published in the journal Global Sustainability, are as follows:

  1. Questions remain about the record warmth in 2023-24
  2. Unprecedented ocean surface warming and intensifying marine heatwaves are driving severe ecological losses
  3. The global land carbon sink is under strain
  4. Climate change and biodiversity loss amplify each other
  5. Climate change is accelerating groundwater depletion
  6. Climate change is driving an increase in dengue fever
  7. Climate change diminishes labour productivity
  8. Safe scale-up of carbon dioxide removal is needed
  9. Carbon credit markets come with serious integrity challenges
  10. Policy mixes outperform stand-alone measures in advancing emissions reductions

In this article, we unpack some of the key findings.

A strained climate system

The first three insights highlight how strains are growing across the climate system, from indications of an accelerating warming and record-breaking marine heatwaves, to faltering carbon sinks.

Between April 2023 and March 2024, global temperatures reached unprecedented levels – a surge that cannot be fully explained by the long-term warming trend and typical year-to-year fluctuations of the Earth’s climate. This suggests other factors are at play, such as declining sulphur emissions and shifting cloud cover.

(For more, Carbon Brief’s in-depth explainer of the drivers of recent exceptional warmth.)

Ocean heat uptake has climbed as well. This has intensified marine heatwaves, further stressing ecosystems and livelihoods that rely on fisheries and coastal resources.

The exceptional warming of the ocean has driven widespread impacts, including massive coral bleaching, fish and shellfish mortality and disruptions to marine food chains.

The map below illustrates some of the impacts of marine heatwaves from 2023-24, highlighting damage inflicted on coral reefs, fishing stocks and coastal communities.

The impacts of the exceptional marine heatwaves over 2023–24, a period which saw the warmest sea surface temperature in the satellite record since 1985.
The impacts of the exceptional marine heatwaves over 2023–24, a period which saw the warmest sea surface temperature in the satellite record since 1985. Dataset used is the ESA Climate Change Initiative’s sea surface temperature v3 featured in Embury et al. (2024). Credit: 10 new insights in climate science report (2025).

Land “sinks” that absorb carbon – and buffer the emissions from human activity – are under increasing stress, too. Recent research shows a reduction in carbon stored in boreal forests and permafrost ecosystems.

The weakening carbon sinks means that more human-caused carbon emissions remain in the atmosphere, further driving up global temperatures and increasing the chances that warming will surpass the Paris Agreement’s 1.5C limit.

This links to the fourth insight, which shows how climate change and biodiversity loss can amplify each other by leading to a decrease in the accumulation of biomass and reduced carbon storage, creating a destabilising feedback loop that accelerates warming.

New evidence demonstrates that climate change could threaten more than 3-6 million species and, as a result, could undermine critical ecosystem functions.

For example, recent projections indicate that the loss of plant species could reduce carbon sequestration capacity in the range of 7-145bn tonnes of carbon over the coming decades. Similarly, studies show that, in tropical systems, the extinction of animals could reduce carbon storage capacity by up to 26%.

Human health and livelihoods

Growing pressure on the climate system is having cascading consequences for human societies and natural systems.

Our fifth insight highlights how groundwater supplies are increasingly at risk.

More than half the global population depends on groundwater – the second largest source of freshwater after polar ice – for survival.

But groundwater levels are in decline around the world. A 2025 Nature paper found that rapid groundwater declines, exceeding 50cm each year, have occurred in many regions in the 21st century, especially in arid areas dominated by cropland. The analysis also showed that groundwater losses accelerated over the past four decades in about 30% of regional aquifers.  

Changes in rainfall patterns due to climate change, combined with increased irrigation demand for agriculture, are depleting groundwater reserves at alarming rates.

The figure below illustrates how climate-driven reductions in rainfall, combined with increased evapotranspiration, are projected to significantly reduce groundwater recharge in many arid regions – contributing to widespread groundwater-level declines.

The top panel shows the impact of climate change on terrestrial water fluxes and groundwater recharge.
The top panel shows the impact of climate change on terrestrial water fluxes and groundwater recharge. It illustrates how climate change directly and indirectly affects groundwater resources by altering precipitation (P) and temperature (T) patterns, increasing evapotranspiration (ET), which further reduces groundwater recharge (R) and leads to declining levels. The lower panel illustrates how lower water tables can cause wells to run dry (B), streams to lose water to surrounding aquifers (C), saltwater to intrude into coastal aquifers (D) and land subsidence (E). Credit: 10 new insights in climate science report (2025).

These losses threaten food security, amplifying competition for scarce resources and undermining the resilience of entire communities.

Human health and livelihoods are also being affected by changes to the climate.

Our sixth insight spotlights the ongoing and projected expansion of the mosquito-borne disease dengue fever.

Dengue surged to the largest global outbreak on record in 2024, with the World Health Organization reporting 14.2m cases, which is an underestimate because not all cases are counted.

Rising temperatures are creating more favourable conditions for the mosquitoes that carry dengue, driving the disease’s spread and increasing its intensity.

The chart below shows the regions climatically suitable for Aedes albopictus (blue line) and Aedes aegypti (green line) – the primary mosquitoes species that carry the virus – increased by 46.3% and 10.7%, respectively, between 1951-60 and 2014-23.

The maps on the right reveal how dengue could spread by 2030 and 2050 under an emissions scenario broadly consistent with current climate policies. It shows that the climate suitable for the mosquito that spreads dengue could expand northwards in Canada, central Europe and the West Siberian Plain by 2050.

The chart on the left shows how climate affects the ability of mosquitoes to spread dengue.
The chart on the left shows how climate affects the ability of mosquitoes to spread dengue. R0 (the basic reproduction) on the y-axis represents the average number of new infections in a completely susceptible population generated by a single new case (adapted from Romanello et al. (2024)).The world maps on the right show how the global risk of dengue transmission is expected to change by 2030 and 2050, measured as the number of months in a year when the climate is suitable for mosquitoes to spread the virus, under the SSP2-4.5 scenario (adapted from Ryan et al. (2019), using CMIP6 climate projections). Credit: 10 new insights in climate science report (2025).

The ongoing proliferation of these mosquito species is particularly alarming given their ability to transmit the zika, chikungunya and yellow fever viruses.

Heat stress is also a growing threat to labour productivity and economic growth, which is the seventh insight in our list.

For example, an additional 1C of warming is projected to expose more than 800 million people in tropical regions to unsafe heat levels – potentially reducing working hours by up to 50%.

At 3C warming, sectors such as agriculture, where workers are outdoors and exposed to the sun, could see reductions in effective labour of 25-33% across Africa and Asia, according to a recent Nature Reviews Earth & Environment paper.

Meanwhile, sectors where workers operate in shaded or indoor settings could also face meaningful losses. This drain on productivity compounds socioeconomic issues and places a strain on households, businesses and governments.

Low-income, low-emitting regions are set to shoulder a greater relative share of the impacts of extreme heat on economic growth, exacerbating existing inequalities.

Action and policy

Our report illustrates not only the scale of the challenges facing humanity, but also some of the pathways toward solutions.

The eighth insight emphasises the critical role of carbon dioxide removal (CDR) in stabilising the climate, especially in “overshoot” scenarios where warming temporarily surpasses 1.5C and is then brought back down.

Scaling these CDR solutions responsibly presents technical, ecological, justice, equity and governance challenges.

Nature-based approaches for pulling carbon out of the air – such as afforestation, peatland rewetting and agroforestry – could have negative consequences for food security, biodiversity conservation and resource provision if deployed at scale.

Yet, research has suggested that substantially more CDR may be needed than estimated in the scenarios used in the Intergovernmental Panel on Climate Change (IPCC’s) last assessment report.

Recent findings showed that a pathway where temperatures remain below 1.5C with no overshoot would require up to 400Gt of cumulative CDR by 2100 in order to buffer against the effect of complex geophysical processes that can accelerate climate change. This figure is roughly twice the amount of CDR assessed by the IPCC.

This underscores the need for robust international coordination on the responsible scaling of CDR technologies, as a complement to ambitious efforts to reduce emissions. Transparent carbon accounting frameworks that include CDR will be required to align national pledges with international goals.

Similarly, voluntary carbon markets – where carbon “offsets” are traded by corporations, individuals and organisations that are under no legal obligation to make emission cuts – face challenges.

Our ninth insight shows how low-quality carbon credits have undermined the credibility of these largely unregulated carbon markets, limiting their effectiveness in supporting emission reductions.

However, emerging standards and integrity initiatives, such as governance and quality benchmarks developed by the Integrity Council for Voluntary Carbon Markets, could address some of the concerns and criticism associated with carbon credit projects.

High-quality carbon credits that are verified and rigorously monitored can complement direct emission reductions.

Finally, our 10th insight highlights how a mix of climate policies typically have greater success than standalone measures.

Research published in Science in 2024 shows how carefully tailored policy packages – including carbon pricing, regulations, and incentives – could consistently achieve larger and more durable emission reductions than isolated interventions.

For example, in the buildings sector, regulations that ban or phase out products or activities achieve an average effect size of 32% when included in a policy package, compared with 13% when implemented on their own.

Importantly, policy mixes that are tailored to the country context and with attention to distributional equity are more likely to gain public support.

These 10 insights in our latest edition highlight the urgent need for an integrated approach to tackling climate change.

The science is clear, the risks are escalating – but the tools to act are available.

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Guest post: 10 key climate science ‘insights’ from 2025

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Adopting low-cost ‘healthy’ diets could cut food emissions by one-third

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Choosing the “least expensive” healthy food options could cut dietary emissions by one-third, according to a new study.

In addition to the lower emissions, diets composed of low-cost, healthy foods would cost roughly one-third as much as a diet of the most-consumed foods in every country.

The study, published in Nature Food, compares prices and emissions associated with 440 local food products in 171 countries.

The researchers identify some food groups that are low in both cost and emissions, including legumes, nuts and seeds, as well as oils and fats.

Some of the most widely consumed foods – such as wheat, maize, white beans, apples, onions, carrots and small fish – also fall into this category, the study says.

One of the lead authors tells Carbon Brief that while food marketing has promoted the idea that eating environmentally friendly diets is “very fancy and expensive”, the study shows that such diets are achievable through cheap, everyday foods.

Meanwhile, a separate Nature Food study found that reforming the policies that reduce taxes on meat products in the EU could decrease food-related emissions by up to 5.7%.

Costs and emissions

The study defines a healthy diet using the “healthy diet basket” (HDB), which is a standard based on nutritional guidelines that includes a range of food groups with the needed nutrients to provide long-term health.

Using both data on locally available products and food-specific emissions databases, the authors estimate the costs and greenhouse gas emissions of 440 food products needed for healthy diets in 171 countries.

They examine three different healthy diets: one using the most-consumed food products, one using the least expensive food products and one using the lowest-emitting food products.

Each of these diets is constructed for each country, based on costs, emissions, availability and consumption patterns.

The researchers find that a healthy diet comprising the most-consumed foods within each country – such as beef, chicken, pork, milk, rice and tomatoes – emits an average of 2.44 kilograms of CO2-equivalent (kgCO2e) and costs $9.96 (£7.24) in 2021 prices, per person and per day.

However, they find that a healthy diet with the least-expensive locally available foods in each country – such as bananas, carrots, small fish, eggs, lentils, chicken and cassava – emits 1.65kgCO2e and costs $3.68 (£2.68). That is approximately one-third of the emissions and one-third of the cost of the most-consumed products diet.

In comparison, a healthy diet with the lowest-emissions products – such as oats, tuna, sardines and apples – would emit just 0.67kgCO2e, but would cost nearly double the least-expensive diet, at $6.95 (£5.05).

This reveals the tradeoffs of affordability and sustainability – and shows that the least-expensive foods tend to produce lower emissions, according to the study.

Dr Elena Martínez, a food-systems researcher at Tufts University and one of the lead authors of the study, tells Carbon Brief this is generally true because lower-cost food production tends to use fewer fossil fuels and require less land-use change, which also cuts emissions.

Ignacio Drake is coordinator of the fiscal and economic policies at Colansa, an organisation promoting healthy eating and sustainable food systems in Latin America and the Caribbean.

Drake, who was not involved in the study, tells Carbon Brief that the research is a “step further” than previous work on healthy diets. He adds that the study “integrates and consolidates” previous analyses done by other groups, such as the World Bank and the UN Food and Agriculture Organization.

Food group differences

The research looks at six food groups: animal-sourced foods, oils and fats, fruits, legumes (as well as nuts and seeds), vegetables and starchy staples.

Animal-sourced foods – such as meat and dairy – are typically the most-emitting, and most-expensive, food group.

Within this group, the study finds that beef has the highest costs and emissions, while small fish, such as sardines, have the lowest emissions. Milk and poultry are amongst the least-expensive products for a healthy diet.

Starchy staple products also contribute to high emissions too, adds the study, because they make up such a large portion of most people’s calories.

Emissions from fruits, vegetables, legumes and oil are lower than those from animal-derived foods.

The following chart shows the energy contributions (top) and related emissions (bottom) from six major food groups in the three diets modelled by the study: lowest-cost (left), lowest-emission (middle) and most-common (right) food items.

The six food groups examined in the study are shown in different colours: animal-sourced foods (red), legumes, nuts and seeds (blue), oils and fats (purple), vegetables (green), fruits (orange) and starchy staples (yellow). The size of each box represents the contribution of that food to the overall dietary energy (top) and greenhouse gas emissions (bottom) of each diet.

Energy (top) and emissions (bottom) contributions from different food groups within the three diets modelled by the study.
Energy (top) and emissions (bottom) contributions from different food groups within the three diets modelled by the study. Each column represents a different diet (left to right): lowest-cost, lowest-emission and most common items. The boxes are coloured by food group: animal-sourced foods (red), legumes, nuts and seeds (blue), oils and fats (purple), vegetables (green), fruits (orange) and starchy staples (yellow). Source: Bai et al. (2025).

Prof William Masters, a professor at Tufts University and author on the study, tells Carbon Brief that balancing food groups is important for human health and the environment, but local context is also important. For example, he points out that in low-income countries, some people do not get enough animal-sourced foods.

For Drake, if there are foods with the same nutritional quality, but that are cheaper and produce fewer emissions, it is logical to think that the “cost-benefit ratio [of switching] is clear”.

Other studies and reports have also modelled healthy and sustainable diets and, although they do not exclude animal-sourced foods, they do limit their consumption.

A recent study estimated that a global food system transformation – including a diet known as the “planetary health diet”, based on cutting meat, dairy and sugar and increasing plant-based foods, along with other actions – can help limit global temperature rise to 1.85C by 2050.

The latest EAT-Lancet Commission report found that a global shift to healthier diets could cut non-CO2 emissions from agriculture, such as methane and nitrous oxide, by 15%. The report recommends increasing the production of fruit, vegetable and nuts by two-thirds, while reducing livestock meat production by one-third.

Dr Sonia Rodríguez, head of the department of food, culture and environment at Mexico’s National Institute of Public Health, says that unlike earlier studies, which project ideal scenarios, this new study also evaluates real scenarios and provides a “global view” of the costs and emissions of diets in various countries.

Increasing access

The study points out that as people’s incomes increase, their consumption of expensive foods also increases. However, it adds, some people with high income that can afford healthy diets often consume other types of foods, due to reasons such as preferences, time and cooking costs.

The study stresses that nearly one-third of the world’s population – about 2.6 billion people – cannot afford sufficient food products required for a healthy diet.

In low-income countries, primarily in sub-Saharan Africa and south Asia, 75% of the population cannot afford a healthy diet, says the study.

In middle-income countries, such as China, Brazil, Mexico and Russia, more than half of the population can afford such a diet.

To improve the consumption of healthy, sustainable and affordable foods, the authors recommend changes in food policy, increasing the availability of food at the local level and substituting highly emitting products.

Martínez also suggests implementing labelling systems with information on the environmental footprint and nutritional quality of foods. She adds:

“We need strategies beyond just reducing the cost of diets to get people to eat climate-friendly foods.”

Drake notes that there are public and financial policies that can help reduce the consumption of unhealthy and unsustainable foods, such as taxes on unhealthy foods and sugary drinks. This, he adds, would lead to better health outcomes for countries and free up public resources for implementing other policies, such as subsidies for producing healthy food.

Separately, another recent Nature Food study looks at taxes specifically on meat products, which are subject to reduced value-added tax (VAT) in 22 EU member states.

It finds that taxing meat at the standard VAT rate could decrease dietary-related greenhouse gases by 3.5-5.7%. Such a levy would also have positive outcomes for water and land use, as well as biodiversity loss, according to the study.

The post Adopting low-cost ‘healthy’ diets could cut food emissions by one-third appeared first on Carbon Brief.

Adopting low-cost ‘healthy’ diets could cut food emissions by one-third

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